Effect of paper mill sludge compost on tissue nutrient concentrations in soybean cultivars

摘要

The objectives of this study were to determine concentrations of major elements in above-ground tissues of soybean [Glycine max (L.) Merr.] as affected by paper mill sludge compost (PMSC) and to ascertain genotypic variation in the concentrations of those elements. The PMSC used in this study was produced from sludge effluent from paper mills, amended with pig manure. Field experiments were conducted on a sandy loam soil with a randomized complete-block design. Three PMSC application rates (0, 75, and 150 mg ha~(-1)) and 30 soybean cultivars were used in this study with four replications. The concentrations of N, P. K, Na, Ca, Mg, Cu, Zn, and Mn, in aboveground tissues harvested 69 days after planting, varied significantly with genotype and/or PMSC application rate. PMSC had a stronger effect on N and P concentrations than did the soybean genotype. We conclude that, to achieve maximum benefits, compost application rate should be based on the specific soybean cultivar grown in the field, rather than a uniform rate for all cultivars.